Method and apparatus for installing or replacing flotation in existing marine structures

ABSTRACT

A method and apparatus for installing flotation, such as polystyrene foam blocks, under existing, floating marine structures is disclosed. The foamed blocks are secured to a floating, ballasted vessel having a controlled water inlet and controlled air inlet connecting to a line open to the atmosphere. Sufficient water is pumped into the vessel to submerge the vessel and the foamed blocks secured to the vessel beneath the surface of the water a sufficient depth to position the blocks under the marine structure in a desired position. Water is then removed from the flotation vessel, allowing air to reenter through the air inlet and allowing the foamed blocks to contact the under surface of the marine structure. The foamed blocks are released from the vessel, the vessel removed from beneath the structure, and refloated to secure additional blocks thereto.

Broadfoot ite States 3113 atent 1 METHOD AND APPARATUS FOR INSTALLING OR REPLACING FLOTATION IN EXISTING MARINE STRUCTURES [76] Inventor: John T. Broadfoot, Star Route 1, Box 144, Kingston, Wash. 98346 [22] Filed: Jan. 2, 1974 [21] Appl. No.: 429,591

[52] US. Cl lI4/0.5 F, l14/0.5 R, 114/16 R,

114/44 [51] Int. Cl 1363b 7/00 [58] Field of Search 114/0.5 F, 44, 49, 52,

114/16 R, 221 R, 44, 53, 50, .5 R, 123, 45, 46, 43.5; 294/64 R, 64 A, 64 B, 65

Primary Examinel'Trygve M. B lix Assistant Examiner-Gregory W. O'Connor Attorney, Agent, or FirmSeed, Berry, Vernon & Baynham [57} ABSTRACT A method and apparatus for installing flotation, such as polystyrene foam blocks, under existing, floating marine structures is disclosed. The foamed blocks are secured to a floating, ballasted vessel having a controlled water inlet and controlled air inlet connecting to a line open to the atmosphere. Sufficient water is pumped into the vessel to submerge the vessel and the foamed blocks secured to the vessel beneath the surface of the water of sufficient depth to position the blocks under the marine structure in a desired position. Water is then removed from the flotation vessel, allowing air to reenter through the air inlet and allowing the foamed blocks to contact the under surface of the marine structure. The foamed blocks are released from the vessel, the vessel removed from beneath the structure, and refloated to secure additional blocks thereto.

10 Claims, 4 Drawing Figures PATENTED MR2 5 I975 FHGO SHEET 1 [IF 2 BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a method and apparatus for replacing or installing flotation under existing, floating marine structures.

2. Prior Art Relating to the Disclosure Foamed blocks, particularly polystyrene foam blocks, are commonly used as flotation for marine structures, particularly dock structures extending out into the water from shorelines. The flotation capability of polystyrene foam tends todeteriorate with age, allowing the dock structure to sink down into the water, necessitating additional flotation. Also, some dock structures are either inadequately installed initially or additional weight put on the dock structure, necessitating additional flotation. Flotation has generally been added by installation of additional blocks of polystyrene foam beneath the floating structure. This requires a diver to correctly locate the foamed blocks and means to sink the foamed blocks beneath the dock structure for location. The foamed blocks are cumbersome to handle and, because of their high flotation capability, are difficult to submerge and locate in place beneath existing floating structures. Another method used for placement of additional flotation is removal of the decking of the dock and location of flotation beneath the dock through openings in the decking. This is both expensive and time-consuming and disrupts the normal use of the dock.

SUMMARY OF THE INVENTION 3 This invention is directed to a method and means of installing or replacing flotation under floating marine structures. Flotation units of foamed polystyrene or other suitable material are secured to a ballasted, floating vessel having a water intake and outlet therein and an air outlet connected to a line open .to the atmosphere. The vessel is filled with water sufficient to submerge the vessel and the flotation units beneath the surface of the water. The submerged flotation units are then located in thedesired position beneath the float-' ing marine structure. Water is then removedfrom the vessel, increasing the floating capability of the vessel to allow the units to contact the under surface of the marine structure. The flotation units are then disconnected from the vessel, the vessel removed from under the marine structure and the vessel refloated for attachment of additional flotation units.

The object of this invention is to provide a system of installing or replacing flotation under existing floating marine structures which (1) is inexpensive, (2) can be accomplished without need of a diver and without need of removing decking from the dock to expose the water beneath, (3) is maintenance free, and (4) involves initial low capital outlay.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates the flotation vessel having flotation units secured thereto above water in a first position and the vessel and flotation units submerged beneath a marine structure in a second position;

FIG. 2 is a schematic diagram of the pump and valving employed to pump water into and out of the flotation vessel; and

FIG. 3 is a schematic representation of the flotation vessel, means of attachment of the flotation units to vacuum pads which are, in turn, attached to the flotation vessel, and a pump for drawing water out of and putting water into the flotation vessel.

FIG. 4 is a schematic representation of the support system for the present invention.

* DETAILED DESCRIPTION OF THE INVENTION Referring to FIG. 2, a vessel 10 of any suitable material, such as plastic-reinforced glass fiber or galvanized steel, is utilized having a water inlet 12 and an air inlet 14. The water inlet is fitted with a pipe 16 extending into the vessel down to the lower end thereof. The air inletis fitted with a pipe 18. A required amount of ballast 20, such as concrete, is poured into or around the lower part of the vessel. In the latter case, the concrete is held to the vessel by a metal framework 22 having legs imbedded in the concrete at one end and crisscrossing over the top of the flotation vessel. An I-beam 24 is secured to the top of the frame of the flotation vessel. Handles 26 are pivotally connected to the frame at 28 of sufficient length to enable a person standing on the raft or dock to locate the flotation vessel beneath a dock structure for placement offlotation units thereunder without necessity'of a diver, although a diver may be used if desired.

Flotation units 29 of foamed polystyrene or other suitable material are secured to the flotation vessel by means of vacuum pads30, illustrated best by FIG. 2. Each of the vacuum pads 30 includes a flat metal plate 31 having upwardly extending flanges around the outer edges thereof. An opening 32 about the center of each steel plate connects to a flexible air line 33. Expanded metal mesh 34 is laid within each of the plates 31. Flexible sealing flaps 35, such as neoprene rubber sheet, are secured around the circumference of the metal plates 31 and extend outwardly. When a vacuum is pulled through line 33, the flotation unit 29 is held to the flotation pad. An effective seal is created between the units 29 and plates 31 by the flexible flaps 35. The vacuum pads are secured to two metal supports 36 (see FIG. 4). The supports 36 are, in turn, attached by swivel attachments 37 to a beam 38 which has downwardly extending projections 39 on each end. thereof fitting into sleeves 40 secured at opposite sides of the vessel to the upper portion of the legs of the frame 22.

Each of the lines from the vacuum pads 33 connects with respective. water aspirators 50, each having a water inlet 51 and a water outlet 52. The water inlets of each aspirator are connected by a common water line 53 leading to a source of pressurized water.

Water is pumped into and out of the flotation vessel to sink it or float it by pump 41. Pump 41 may be powered manually or by an electric or gasoline motor. The intake end 42 and discharge end 43 of the pump are connected through suitable lines to three port, two-way valves 44 and 45. The intake end 42 of the pump may be connected to a strainer 46 for straining debris from the incoming water. The valves 44 and are connected together by lines 47 and 48 in the manner shown by FIG. 2. Line 49 leading from connecting line 47 connects to the water inlet 12 of the vessel. Line 49a leading from connecting line 48 leads to a source of water.

Replacement or installation of flotation units under existing marinestructures such as a dock 56 is best accomplished using a floating barge 55 which has an inlet cut therein of sufficient size to receive the flotation vessel and vacuum pads. Referring to FIG. 1 inches and barge 55 and flotation vessel are positioned adjacent an existing marine structure 56 where additional flotation is needed The vessel with vacuum pads attached is placed in the water in theslot of the barge. Pressurized water at 50-100 psi is forced through the water aspirators 50, applying suction through each of the vacuum pads 30. Foamed blocks of polystyrene or other suitable flotation units 29 are positioned over the pads and held thereto by'the generated vacuum. The vacuum pads are generally 12 X 40 and are designed to secure a 12 to 18 cubic foot block. The aspirators are capable of pulling 15 to inches of vacuum. Valves 44 and 45 are positioned to pump water into the flotation vessel 10 by pump 41 until the weight of the water, in addition to that of theballast 20, sinks the flotation units secured to the vacuum pads. The operator, by means of the handles 26, positions the flotation vessel and flotation units beneath the dock in the position desired. Valves 44 and 45 are then positioned and pump 41 energized to pump water out of the flotation vessel, allowing air to reenter the vessel through a line connected at one end to the air inlet 18 and open at the other end to the atmosphere. Sufficient water is removed to allow the flotation vessel and flotation units attached thereto to slowly ascend under the dock structure to the position desired. Once the flotation units are correctly located in place, the vacuum on the vacuum pads is cut off by turning off the water going through the water aspirators 50, allowing release of the flotation units. If necessary, additional water may be pumped into the flotation vessel to lower it in the water sufficiently for removal from beneath the dock structure. The vessel is then repositioned in the inlet or slot of the barge and water pumped out of the flotation vessel sufficient to refloat the vacuum pads and the flotation vessel. Additional flotation units are replaced or installed in the same manner described. Using the method and apparatus described, as much as 10,000 cubic feet of flotation can be installed under a dock in one day at considerably reduced costs over the methods previously employed.

The barge shown is about 8 X 8 and is small enough to work around an existing dock structure for replacement of flotation without disrupting the normal activity generally found around a marina. The flotation vessel illustrated with the concrete ballast attached, weighs about 3,300 pounds, dry weight, and 1,800 to 2,000 pounds in the water. When nearly filled'with water, the vessel has the capability of submerging two flotation units of foamed polystyrene, each having a volume of 12 to 18 cubic feet.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. An in situ method of installing flotation units under floating marine structures, comprising:

providing a floating vessel in the water adjacent the marine structure,

temporarily securing one or more flotation units to be installed under the floating marine structure to the vessel,

adding ballast to the vessel sufficient to suspend the vessel and connected flotation units beneath the water at a level to clear the underside of the marine structure,

locating the flotation units in the desired position beneath the floating marine structure,

removing ballast from the vessel, allowing the flotation units to ascend in the water and contact the underside of the marine structure in the position desired, releasing the flotation units from the vessel, and removing the vessel from'beneath the floating marine structure.

2. The method of claim 1 including removing sufficient ballast from the vessel after release of the flotation units to refloat the vessel adjacent the marine structure for securing additional flotation units thereto.

3. The method of claim 2 wherein the flotation units are secured to the flotation vessel by vacuum' and released by removal of the vacuum.

4. The method of claim 1 wherein the ballast is added to the vessel by displacing air therein with water and the ballast is removed by displacing the water therein with air.

5. A method of installing additional foamed flotation blocks under floating marine structures, comprising: I

providing a ballasted, hollow, floating vessel having vacuum pads attached thereto in the water adjacent the marine structure,

temporarily securing by vacuum one or more foamed flotation blocks to the vacuum pads,

displacing air in the vessel with water to add sufficient ballast to the vessel to sink and suspend the vessel and secured foamed blocks beneath the water at a level to clear the underside of the marine structure,

locating the foamed blocks beneath the marine structure in the desired location,

displacing-water in the vessel with sufficient air to allow the vessel and foamed blocks to rise in the water and-the blocks to contact the underside of the marine structure,

releasing the foamed blocks by shutting off the vacuum to the vacuum pads, removing the vessel and attached vacuum pads from beneath the marine structure, and

displacing sufficient water in the vessel with air to refloat the vessel and pads for securing additional foamed flotation blocks thereto.

6. Apparatus for installing new or additional flotation capacity under existing, floating marine structures, comprising:

a floating vessel,

vacuum pads for releasably securing flotation units to be positioned under an existing marine structure to the floating vessel, and

means for l adding sufficient ballast to the floating vessel to suspend the vessel and flotation units beneath the water at a level to clear the underside of the marine structure to position the flotation units and then (2) removing ballast from the floating vessel until the flotation units ascend to contact the 4 underside of the marine structure.

7. The apparatus of claim 6 wherein the vacuum pads include vacuum means drawing a vacuum on the pads to secure the flotation units to the pads by negative pressure.

8. The apparatus of claim 6 wherein the vessel has a first opening provided with a first conduit extending thereinto to the lower end thereof, and a second opening provided with a conduit opening to the atmosphere, and wherein the means for adding and removing ballast is a water pump connected between the first conduit and a source of water.

9. The apparatus of claim 7 wherein the vacuum means are water aspirators connected to a source of water under pressure.

10. Apparatus for installing flotation in the form of foamed synthetic blocks under existing, floating marine structures, comprising:

a ballasted, hollow vessel having a first opening provided with a conduit for water extending thereinto to near the lower end of the vessel and a second opening provided with an air conduit opening to the atmosphere,

pump means connected between the water conduit and a source of water for pumping water into the vessel to displace air therein through the air conduit and for pumping water out of the vessel to allow air to reenter the vessel through the air conduit as a means of adding ballast to and removing ballast from the vessel,

vacuum pads pivotally connected to the vessel, each pad including a planar body portion and a flexible sealing flap surrounding the body portion,

one or more water aspirators having an air inlet connected to the vacuum pads, and water inlet and discharge ports, and

means connecting the water inlets of the aspirators to a source of water under pressure, water flow through the aspirators resulting in generation of a negative pressure in the air inlet. 

1. An in situ method of installing flotation units under floating marine structures, comprising: providing a floating vessel in the water adjacent the marine structure, temporarily securing one or more flotation units to be installed under the floating marine structure to the vessel, adding ballast to the vessel sufficient to suspend the vessel and connected flotation units beneath the water at a level to clear the underside of the marine structure, locating the flotation units in the desired position beneath the floating marine structure, removing ballast from the vessel, allowing the flotation units to ascend in the water and contact the underside of the marine structure in the position desired, releasing the flotation units from the vessel, and removing the vessel from beneath the floating marine structure.
 2. The method of claim 1 including removing sufficient ballast from the vessel after release of the flotation units to refloat the vessel adjacent the marine structure for securing additional flotation units thereto.
 3. The method of claim 2 wherein the flotation units are secured to the flotation vessel by vacuum and released by removal of the vacuum.
 4. The method of claim 1 wherein the ballast is added to the vessel by displacing air therein with water and the ballast is removed by displacing the water therein with air.
 5. A method of installing additional foamed flotation blocks under floating marine structures, comprising: providing a ballasted, hollow, floating vessel having vacuum pads attached thereto in the water adjacent the marine structure, temporarily securing by vacuum one or more foamed flotation blocks to the vacuum pads, displacing air in the vessel with water to add sufficient ballast to the vessel to sink and suspend the vessel and secured foamed blocks beneath the water at a level to clear the underside of the marine structure, locating the foamed blocks beneath the marine structure in the desired location, displacing water in the vessel with sufficient air to allow the vessel and foamed blocks to rise in the water and the blocks to contact the underside of the marine structure, releasing the foamed blocks by shutting off the vacuum to the vacuum pads, removing the vessel and attached vacuum pads from beneath the marine structure, and displacing sufficient water in the vessel with air to refloat the vessel and pads for securing additional foamed flotation blocks thereto.
 6. Apparatus for installing new or additional flotation capacity under existing, floating marine structures, comprising: a floating vessel, vacuum pads for releasably securing flotation units to be positioned under an existing marine structure to the floating vessel, and means for (1) adding sufficient ballast to the floating vessel to suspend the vessel and flotation units beneath the water at a level to clear the underside of the marine structure to position the flotation units and then (2) removing ballast from the floating vessel until the flotation units ascend to contact the underside of the marine structure.
 7. The apparatus of claim 6 wherein the vacuum pads include vacuum means drawing a vacuum on the pads to secure the flotation units to the pads by negative pressure.
 8. The apparatus of claim 6 wherein the vessel has a first opening provided with a first conduit extending thereinto to the lower end thereof, and a second opening provided with a conduit opening to the atmosphere, and wherein the means for adding and removing ballast is a water pump connected between the first conduit and a source of water.
 9. The apparatus of claim 7 wherein the vacuum means are water aspirators connected to a source of water under pressure.
 10. Apparatus for installing flotation in the form of foamed synthetic blocks under existing, floating marine structures, comprising: a ballasted, hollow vessel having a first opening provided with a conduit for water extending thereinto to near the lower end of the vessel and a second opening provided with an air conduit opening to the atmosphere, pump means connected between the water conduit and a source of water for pumping water into the vessel to displace air therein through the air conduit and for pumping water out of the vessel to allow air to reenter the vessel through the air conduit as a means of adding ballast to and removing ballast from the vessel, vacuum pads pivotally connected to the vessel, each pad including a planar body portion and a flexible sealing flap surrounding the body portion, one or more water aspirators having an air inlet connected to the vacuum pads, and water inlet and discharge ports, and means connecting the water inlets of the aspirators to a source of water under pressure, water flow through the aspirators resulting in generation of a negative pressure in the air inlet. 